First electromyographic monitoring of a progressive phrenic nerve palsy in a pulsed field ablation procedure

Right phrenic nerve palsy (PNP) is a usual complication of atrial fibrillation ablation procedures, in particular with cryoballoon1. PNP is a specific complication of Pulsed Field Ablation either2,3. Several cases of persistent PNP were described2,3. It should be noticed that no phrenic nerve monitoring was performed in these studies, thus PNP incidence could have been underestimated. Moreover, nothing is known about the mechanism and the mode of occurrence of this complication. What is the onset pattern (sudden or progressive)? Is it dose-dependent? Can-it be prevented? Several years ago, we developed a specific right phrenic nerve monitoring approach with CMAP during cryoballoon procedures4.